Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3e8f0e90ee34af8…

MALICIOUS

PDF

82.1 KB Created: 2021-09-17 13:54:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cc5d1a7789370cd401d002b98e79353b SHA-1: fbf2639d7439633636d61ffcf2cc508f3f6a9753 SHA-256: a3e8f0e90ee34af85603e3c81b4a13c8a7857749c269d13754499223096ea231
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF file flagged by ClamAV as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to potentially malicious content. The ML classifier also strongly suggests maliciousness. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://randoquad72.fr/userfiles/file/nevutivunupugirobubut.pdf In PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1612ede471ca0a---56569327916.pdfIn PDF document text
    • http://xn--h49al33a2zdp0eo1x.com/DATA/file/20210913151439.pdfIn PDF document text
    • https://showdetango.com/bafa/userfiles/file/pigasagafufuvajitolojil.pdfIn PDF document text
    • http://eventclub.pl/userfiles/file/90318077352.pdfIn PDF document text
    • http://zhjpharm.com/upload/files/86336924477.pdfIn PDF document text
    • http://thaihotelsale.com/FileData/ckfinder/files/20210914_B072E131829DE46B.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/1tcts66bmu3fos5og8vdegiu9o/pinikixefexokemubarasir.pdfIn PDF document text
    • http://tythb.cn/uploadfile/files/zafuxuja.pdfIn PDF document text
    • https://bdprescription.com/ci/userfiles/files/votaburaledadokolu.pdfIn PDF document text
    • http://business-plan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/34240605153.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/mositerikuwapofugenevan.pdfIn PDF document text
    • http://heaig.org/editor/ckfinder/userfiles/files/bevofebirafu.pdfIn PDF document text
    • http://iktoktatas.hu/files/file/voxozeduzopuwafur.pdfIn PDF document text
    • http://cybernet-ap.com/UserFiles/File/waweb.pdfIn PDF document text
    • https://kawanmto.net/contents/files/kumezu.pdfIn PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/97808599935.pdfIn PDF document text
    • https://cuatudongnhatrang.com/uploads/files/14832670118.pdfIn PDF document text
    • http://bienbao.net/uploads/files/46305552365.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/11893428267.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/nawumusuf.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210916180421.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/51038895769.pdfIn PDF document text
    • http://gsmontaggi.it/userfiles/files/pazigakusuximilofesugime.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/jevobotajomikoregipew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=windroy+windows+7+32+bitPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5EC 17444 bytes
SHA-256: 499643ff16afe36e7e0ae3cfecd4f196b74c062f434ce6399c9fd8d7c79aa098
font_02_sfnt_off000122ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122EC 10576 bytes
SHA-256: dec97b94ae7d07fac681a4641127cfc92d0bbe55c326609e8d617c11cfa02648